Hydrostatic workpiece holders utilize hydrostatic pressure to expand a metal sleeve, which exerts a holding pressure on a workpiece. U.S. Pat. No. 6,015,154 discloses a hydrostatic holding device comprising a fluid chamber defined, at least in part, by a bladder or bladder. The bladder separates the fluid in the chamber from the sleeve and prevents the fluid in the chamber from escaping. While the device is effective and reliable as a workpiece holder, improvements are necessary to reduce leakage from the fluid chamber and further to increase the performance and durability of the device.